If there is any rattling, its a LOT less than previously
I haven;t yet tried anything to seal the U-tube better, I was going to wrap some thick tape around the end of the U, and then cram it in and see if it seals. If it didn't I was going to try some RTV. But the ball peen hammer idea would work too...it was a very small amount of interference. I actually have a ball peen hammer, I might give it a try this weekend. Otherwise, I'll make another trip over in another couple weeks...well, maybe in early spring, it might be too nippy to be messing with this in the winter.